Salps of the Southern Ocean (Australian Sector) during the 1983-84 summer, with special reference to the species Salpa thompsoni, FOXTON 1961

• Main Authors: Casareto,Beatriz Estela, Nemoto,Takahisa
• Format: Report
• Language: English
• Published: Ocean Research Institute, University of Tokyo/Ocean Research Institute, University of Tokyo 1986
• Subjects: Antarctic; Southern Ocean; Thalia; Antarc*; Memoirs of National Institute of Polar Research; Polar Research
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=1894; http://id.nii.ac.jp/1291/00001894/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=1894&item_no=1&attribute_id=18&file_no=1

Studies on salps were carried out on the plankton samples collected by R. V. HAKUHO MARU during the KH-83-4 cruise in the Southern Ocean (Australian Sector) as part of the BIOMASS SIBEX I programme. The geographical distribution of salps showed that widely distributed cosmopolitan species such as Salpa fusiformis, Salpa aspera, Thalia democratica and Pegea confoederata reached their southern limit at the Subtropical Convergence. This boundary represents the northern limit for Salpa thompsoni, the most abundant salp of the Southern Ocean. Ihlea racovitzai was limited to the high latitude Antarctic water. Analysis of stratified samplings performed day and night revealed a pattern of diel vertical migration for Salpa thompsoni, Salpa fusiformis and Ihlea magalhanica. Ihlea racovitzai did not show a clear vertical movement between the day time and the night time. The vertical distribution of Ihlea magalhanica and Ihlea racovitzai appeared to extend deeper than the range determined previously. A pattern of vertical stratification in the size composition and stages of maturity for both aggregate and solitary forms of Salpa thompsoni was observed. Moreover, a comparison of the population at different latitudes revealed different compositions.